AP Photo/Rick BowmerTexas coach Mack Brown said Saturday's loss to BYU was unacceptable and that led to making the change at defensive coordinator.

Robinson was up past 1 a.m. cramming for his first big test as the new leader of the troubled Texas defense. He was still catching up on Texas’ defensive terminology on Monday. He is, understandably, too busy to do interviews with Texas media this week, and Brown said Monday he hadn’t even met with Robinson to talk scheme and planning for Ole Miss.

“He’ll have three practices between now and Saturday to try to get us in a better spot,” Brown said. “It’s a tough deal for him.”

It’s a tough deal for everyone in this Longhorn program. Usually these kinds of coaching changes are made on bye weeks. Brown let Diaz go Sunday in part because he had to buy as much time as he can to get Robinson ready for Texas’ Big 12 schedule.

The biggest reason may have been this: Brown couldn’t afford to sit back and watch things get even worse.

“That was unacceptable on Saturday night,” Brown said. “It went back to the three to four games we had in a row last year where we couldn’t stop the run. I wasn’t going to let that continue.”

He does not expect Robinson to work a miracle and fix every flaw in one week. Brown just needs to see progress, and the veteran leaders of his defense are ready to get to work once they get their game plan.

“Obviously right now, we’re not sure what the game plan is,” Texas linebacker Jordan Hicks said. “Coach Robinson, coach [Duane} Akina, coach [Bo] Davis are all in there getting all the film sessions and game plans ready to go. The biggest thing we’ve got to do is execute. We felt prepared for BYU. We were prepared. We’ve got to go out there and put it on ourselves to actually execute a game plan and do that effectively.”

Hicks admitted he was shocked Diaz was let go but believes his former position coach would want the team to move on and get ready for No. 25 Ole Miss.

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Brown said Monday the plan Texas had to attack BYU was a good one. The players’ inconsistent execution of that plan was the real problem, and their coach was held responsible for that.

“If we would’ve performed better, if we would’ve executed his scheme better, he wouldn’t be in this position and we wouldn’t be in this position,” Hicks said. “We feel like we could’ve played better against BYU and had better opportunities.”

Brown saw enough from working with Robinson in 2004 to know he’s the kind of guy Texas’ defenders need right now.

“Greg brings a wealth of knowledge. He’s a true veteran,” Brown said. “He’s a guy that has three Rose Bowl rings and a Super Bowl ring, so he’s been there before. He handles pressure well, he makes great adjustments. When he was here before, we tackled very well, we chased the ball and we were very sound fundamentally. He’s a guy kids love to play for.”

The big question is how different his take on Texas’ defense will be. Expect a more simplified approach focused on sound tackling and physical play, and Robinson will add his own wrinkles along the way. But there isn’t enough time at this point to implement sweeping big-picture changes.

“I guess we’ll have to see,” Hicks said. “I don’t know what to expect defensively. I’m not sure if we’re sticking with the same stuff or taking it in a new direction. I have no clue. We haven’t talked about it yet.”

To Texas safety Adrian Phillips, losing Diaz was just as painful as losing in Provo. Both results, he said, felt like a punch in the face. But he felt Robinson made a great impression in his first time meeting with the team Sunday night, and he’s confident his teammates will rally around their new boss.

“I mean, we have no choice,” Phillips said. “If we want BYU to be our only loss of the season, we have no choice but to buy in. I know my teammates want to be successful just like I do. We’ll buy into it.”

What exactly did Robinson say to his new players in his first night on the job?

“He was very brief with them,” Brown said. “He said, ‘Tough situation for all of us. I’m going to come in and try to do the best I can do to help get back on track.’ He broke them down. That was it.”

With less than 140 hours to repair Texas’ defense, he didn’t have time for much else.